cd /etc/apt
cp sources.list sources.list.backup
rm -rf sources.list
echo "# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-free
# deb-src http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-free
deb http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-free
# deb-src http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-free

deb http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-free
# deb-src http://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-free

deb http://mirrors.tuna.tsinghua.edu.cn/debian-security bullseye-security main contrib non-free
# deb-src http://mirrors.tuna.tsinghua.edu.cn/debian-security bullseye-security main contrib non-free" >> sources.list
apt update
apt install apt-transport-https ca-certificates
rm -rf sources.list
echo "# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-free
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye main contrib non-free
deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-free
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-updates main contrib non-free

deb https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-free
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian/ bullseye-backports main contrib non-free

deb https://mirrors.tuna.tsinghua.edu.cn/debian-security bullseye-security main contrib non-free
# deb-src https://mirrors.tuna.tsinghua.edu.cn/debian-security bullseye-security main contrib non-free" >> sources.list
apt update